Greeting,
I'm currently tuning my sxr for this year. I just installed a dry pipe and use the jets provided from Factory Pipe (152.5 main and 80 pilot). My sxr has stock motor with TBM flywheel and stock carburetors. I also switched the stock n/s (1.5) to a 2.0 because the pop off pressure was a bit too high.
The idling to 2/3 throttle is pretty much dead on. It's the high speed that is lean according to the spark plugs. I increased the main jet to 155 and the plugs is bit darker now but still a little lean. My sxr ran great and smooth. I couldn't feel any hiccups, hesitations, and load-ups during the test drive. It is just the high speed (2/3 throttle to WOT) that is lean. The spark plugs are brown-ish and wet from idling to 2/3 throttle (A little rich, but safe). 2/3 to WOT are light brown and dry. I have some 157.5 main jets and probably will try them out to see if that improves.
From my research, I noticed that several people up the pilot jets much higher than what I have in my sxr. Even some are higher than the main jets. I'm trying to understand why are they using bigger pilot jets and lower main jets. I mean the 80 pilot jets I have in my sxr seem to be dead on from 1/3 to 2/3 throttle. I understand that pilot jet delivers fuel all the way to 100% throttle but there is a difference between fuel delivery and fuel metering. I also know that if I want to increase the pilot jet, the main jet must have equal decrease to retain the same mixture.
I have a couple of 87.5 pilot jets lying around. But I'm not certain whatever to increase the main or increase the pilot ever since I learned of several skis with higher pilot jets.
I'm currently tuning my sxr for this year. I just installed a dry pipe and use the jets provided from Factory Pipe (152.5 main and 80 pilot). My sxr has stock motor with TBM flywheel and stock carburetors. I also switched the stock n/s (1.5) to a 2.0 because the pop off pressure was a bit too high.
The idling to 2/3 throttle is pretty much dead on. It's the high speed that is lean according to the spark plugs. I increased the main jet to 155 and the plugs is bit darker now but still a little lean. My sxr ran great and smooth. I couldn't feel any hiccups, hesitations, and load-ups during the test drive. It is just the high speed (2/3 throttle to WOT) that is lean. The spark plugs are brown-ish and wet from idling to 2/3 throttle (A little rich, but safe). 2/3 to WOT are light brown and dry. I have some 157.5 main jets and probably will try them out to see if that improves.
From my research, I noticed that several people up the pilot jets much higher than what I have in my sxr. Even some are higher than the main jets. I'm trying to understand why are they using bigger pilot jets and lower main jets. I mean the 80 pilot jets I have in my sxr seem to be dead on from 1/3 to 2/3 throttle. I understand that pilot jet delivers fuel all the way to 100% throttle but there is a difference between fuel delivery and fuel metering. I also know that if I want to increase the pilot jet, the main jet must have equal decrease to retain the same mixture.
I have a couple of 87.5 pilot jets lying around. But I'm not certain whatever to increase the main or increase the pilot ever since I learned of several skis with higher pilot jets.
